What is the effect of propeller side force during vessel maneuvers?

• A. It increases speed
• B. It causes sterns to veer towards each other
• C. It decreases rudder efficiency
• D. It stabilizes the vessel’s course

Answer: (B)

The effect of propeller side force during vessel maneuvers is that it causes the sterns of the vessels to veer towards each other. This phenomenon occurs due to the torque generated by the rotating propeller, which applies lateral forces on the hull of the vessel. As a result, during operations such as turning or maneuvering in close quarters, the propeller side force can cause the stern to move sideways relative to the bow, leading to the veering of sterns towards each other, especially when vessels are operating in close proximity.

Understanding this side force is crucial for safe navigation and effective maneuvering in congested waters or during docking procedures. The ability to anticipate how the vessel will behave in response to propeller side force allows the Officer of the Deck to make more informed decisions, ensuring the safety of the vessel and those nearby.